Clean air engines transportation and other power applications

ABSTRACT

A low or no pollution engine is provided for delivering power for vehicles or other power applications. The engine has an air inlet which collects air from a surrounding environment. The air is compressed through multiple stages of compression with intercoolers between the compressors. The air is then purged of any constituents which have a relatively high freezing point in a scrubber and then expanded in a turboexpander which causes the air to be cooled down to near air liquifaction temperatures. The air is then passed through a rectifier, where nitrogen is removed from the air. The remaining air is substantially entirely oxygen, which is then compressed and routed to a gas generator. The gas generator has an igniter and inputs for the high pressure oxygen and a high pressure hydrogen containing fuel, such as hydrogen or methane. The fuel and oxygen are combusted within the gas generator, forming water and possibly carbon dioxide. Water is also delivered into the gas generator to control a temperature of the combustion products. The combustion products are then expanded through a power generating device, such as a turbine or piston expander to deliver output power for operation of a vehicle or other power uses. The combustion products, steam and carbon dioxide, are then passed through a condenser where the steam is condensed and the carbon dioxide is collected or discharged. A portion of the water is discharged into the surrounding environment and the remainder is routed back to the gas generator.

FIELD OF THE INVENTION

This invention contains environmentally clean engine designs that emitzero or very low pollutant levels during operation. The CLEAN AIR ENGINE(CLAIRE) invention is directly applicable to transportation typevehicles including automobiles, trucks, trains, ships and stationarystand by power generation applications. The designs feature hybrid, dualcycle and single cycle engines.

BACKGROUND OF THE INVENTION

The current art in generating power for transportation purposesbasically utilize the internal combustion gas or diesel engine. Theseengines burn hydrocarbon fuels with air which contains (by weight) 23.1%oxygen, 75.6% nitrogen and the remaining 1.3% in other gases. Theemissions resulting from the combustion of fuels for internal combustionengines (gasoline or diesel), with air contain the following pollutantsthat are considered damaging to our air environment. These smog causingpollutants, are: total organic gases (TOG); reactive organic gases(ROG); carbon monoxide (CO); oxides of nitrogen (NO_(x)); oxides ofsulfur (SO_(x)); and particulate matter (PM). Approximately one half ofthe total pollutants emitted by all sources of air pollution inCalifornia are generated by road vehicles (Emission Inventory 1991,State of California Air Resources Board, prepared January 1994). Themajor source of this vehicle pollution comes from passenger cars andlight to medium duty trucks.

No near term solutions appear in sight to drastically reduce the vastamount of air pollutants emitted by the many millions of automobiles andtrucks operating today. Based on the State of California Air ResourcesBoard study, the average discharge per person in California of the airpollutants from mobile vehicles, monitored by this agency during 1991and reported in 1994, was approximately 1.50 lb/day per person. With anationwide population of over 250,000,000 people, this data extrapolatesto over 180,000 tons of air borne emissions per day being discharged inthe USA by mobile vehicles. Also, the number of cars and miles that arebeing driven continue to increase, further hampering efforts to reducesmog causing pollutants.

Allowable emission thresholds are rapidly tightening by Federal andState mandates. These allowable emission reductions are placing severedemands on the transportation industry to develop new and lower emissionpower systems such as electric or hybrid vehicles that utilize both anelectric motor and a gas turbine or internal combustion (IC) engine. Inhybrid vehicles, the gas turbine or IC engine can be used directly todrive the vehicle when the electric motor is not in use, due to lowbattery charge (long travel distances), or it can be used indirectly. Inindirect use, vehicle runs off of batteries powering an electric motoruntil the batteries run out of power. The gas turbine or IC engine isthen connected to an alternator to drive the electric motor until theelectric motor battery is recharged, either by the gas turbine or ICengine or a stationary source of electricity. This type of hybridvehicle does not drastically reduce the air pollution emission problem.

Although considerable effort is being directed at improving the range ofelectric zero emission vehicles (ZEV) by developing higher energycapacity, lower cost storage batteries, the emission problem is beentransferred from the vehicle to the electric power generating plant,which is also being Federally mandated (Clean Air Act Amendments of1990) to reduce the same air toxic emissions as those specified forautomobiles and trucks.

Other energy sources being developed to solve the emissions problem, byexploiting non-combustible energy sources include fuel cells and solarcells. Developers are solving many of the technological and economicproblems of these alternate sources. However, widespread use of theseenergy sources for vehicles does not appear to yet be practical.

SUMMARY OF THE INVENTION

This invention provides a means for developing a zero pollution vehicle(ZPV) and other transportation power systems (i.e. rail and ship),comparable to the environmental cleanliness of zero emission electricvehicles (ZEV) and utilizes various thermal cycles. The zero pollutionis achieved by removing the harmful pollutants from the incoming fueland oxidizer reactants prior to mixing and burning them in a gasgenerator or combustion chamber. Sulfur, sulfides and nitrogen are majorpollutants that must be removed from the candidate fuels: hydrogen,methane, propane, purified natural gas, and light alcohols such asethanol and methanol. Since air contains 76% nitrogen by weight, itbecomes a major source of pollution that also requires removal prior tocombining it with the clean fuel. Cleansing of the fuel isstraightforward and requires no further elaboration. The separation ofthe oxygen from the nitrogen in the air, however, is accomplished mostefficiently by the liquefaction of air and gradual separation of the twomajor constituents, oxygen and nitrogen, by means of a rectifier (to bedescribed later in more detail). The separation of the gases relies onthe two distinct boiling points for oxygen (162° R) and for nitrogen139° R at atmospheric pressure. Air liquefies at an intermediatetemperature of 142° R.

One embodiment of this invention consists of a hybrid power system thatcombines a Rankine cycle thermal cycle with an auxiliary electric motorfor startup and chill-down requirements. The thermal power cycle of theengine begins by compressing ambient air to high pressures, cooling theair during compression and during the expansion to liquid airtemperatures in a rectifier where separation of the oxygen and nitrogentakes place. The cold gaseous nitrogen generated is used to cool theincoming air and then discharged to the atmosphere at near ambienttemperature. Simultaneously, the cold gaseous or liquid oxygen generatedby the rectifier is pressurized to gas generator pressure levels anddelivered to the gas generator at near ambient temperature. Fuel,gaseous or liquid, from a supply tank is pressurized to the pressurelevel of the oxygen and also delivered to the gas generator where thetwo reactants are combined at the stoichiometric mixture ratio toachieve complete combustion and maximum temperature hot gases (6500° R).These hot gases are then diluted with water downstream in a mixingsection of the gas generator until the resulting temperature is loweredto acceptable turbine inlet temperatures (2000° R).

The drive gas generated from this mixing process consists of high puritysteam, when using oxygen and hydrogen as the fuel, or a combination ofhigh purity steam and carbon dioxide (CO₂), when using oxygen and lighthydrocarbon fuels (methane, propane, methanol, etc.). Following theexpansion of the hot gas in the turbine, which powers the vehicle, thesteam or steam plus CO₂ mixture are cooled in a condenser to near orbelow atmospheric pressure where the steam condenses into water, thuscompleting a Rankine cycle. Approximately 75% of the condensed water isrecirculated to the gas generator while the remainder is used forcooling and discharged to the atmosphere as warm water vapor. When usinglight hydrocarbons as the fuel, the gaseous carbon dioxide remaining inthe condenser is compressed to slightly above atmospheric pressure andeither converted to a solid or liquid state for periodic removal, or thegas can be discharged into the atmosphere when such discharge isconsidered non-harmful to the local air environment.

Since this thermal cycle requires time to cool the liquefactionequipment to steady state low temperatures, an electric motor, driven bya small auxiliary battery, can be used to power the vehicle and initiatethe Rankine cycle until chill-down of the liquefaction equipment isachieved. When chill-down is complete the thermal Rankine engine,connected to an alternator, is used to power the vehicle and rechargethe auxiliary battery.

The combination of these two power systems, also referred to as a hybridvehicle, emit zero pollution in either mode of operation. In addition,the electric motor battery is charged by the zero pollution thermalRankine cycle engine itself and thus does not require a separateelectric power generating plant for recharge. This reduces the powerdemand from central power stations and also reduces a potential sourceof toxic air emissions.

In place of the electric drive motor and battery, the Rankine cycleengine, with the addition of a few control valves, can also be operatedas a minimally polluting open Brayton cycle, burning fuel and incomingair to power the vehicle during the period necessary to allow theRankine cycle engine liquefaction equipment time to chill-down. Thisfeature is another embodiment of this invention.

The zero pollution Rankine cycle engine can also be used in a singlecycle thermal mode for vehicles with long duration continuous duty suchas heavy trucks, trains, ships and stationary power generation plantswhere the chill-down time is not critical to the overall operationalcycle.

The adaptation of the Otto and Diesel thermal cycles to a low-pollutinghybrid engine are also included as embodiments of this invention. Byusing these thermal cycles, the need for a condenser and recirculatingwater system are eliminated. Low temperature steam or steam/carbondioxide gases are recirculated as the working fluid and thereforereplace the function of the recirculating water quench of the Rankinecycle embodiments previously discussed.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of this invention, which are defined bythe appended claims, will become apparent from consideration of thefollowing drawings:

FIG. 1 is a schematic illustrating an embodiment of this invention andits elements, along with their connectivity. This embodiment constitutesa pollution-free hybrid power system for vehicular and otherapplications. The fuel reactant is a light hydrocarbon type such asmethane propane, purified natural gas, and alcohols (i.e. methanol,ethanol).

FIG. 2 is a schematic illustrating an embodiment of this invention whichis also a pollution-free hybrid power system for vehicular and otherapplications where the fuel is gaseous hydrogen.

FIG. 3 is a schematic illustrating an embodiment of this invention whichis a pollution-free power system for vehicular and other applicationsduring cruise and continuous duty. During start-up and a short periodthereafter, the engine runs in an open Brayton cycle mode and thus emitssome pollutants.

FIG. 4a is a plot of Temperature v. Entropy for the working fluidillustrating the first of two cycles used in the dual mode engine ofFIG. 3. This cycle is an open Brayton with inter-cooling betweencompressor stages (Mode I).

FIG. 4b is a plot of Temperature v. Entropy for the working fluidillustrating the second cycle used in the dual mode engine of FIG. 3.This cycle is a Rankine with regeneration, (Mode II).

FIG. 5 is a schematic illustrating an embodiment of this invention andits interconnecting elements. This embodiment constitutes apollution-free hybrid power system for vehicular and other applicationssimilar to that of FIG. 1 but with the addition of two reheaters to thepower cycle for improved performance. The fuel reactant for this cycleis a light hydrocarbon.

FIG. 6 is a schematic illustrating an embodiment of this invention andits interconnecting elements. This embodiment constitutes apollution-free hybrid power system similar to that of FIG. 2 but withthe addition of two reheaters to the power cycles for improvedperformance. The fuel reactant for this cycle is hydrogen.

FIG. 7 is a plot of Temperature v. Entropy for the working fluid for thepower cycle used for the thermal engines shown in FIG. 5 and FIG. 6.This cycle features the Rankine cycle with regeneration and reheat forimproved performance.

FIG. 8 is a schematic illustrating an embodiment of this invention thatfeatures a non-polluting hybrid engine with electric motor drive and aRankine power cycle utilizing dynamic type turbomachinery. The Rankinepower cycle utilizes regeneration and reheaters for increased cycleefficiency and power density.

FIG. 9 is a schematic illustrating an embodiment of this invention thatfeatures a low-polluting hybrid engine with an electric motor drive andan Otto power cycle reciprocating engine.

FIG. 10 is a schematic illustrating an embodiment of this invention thatfeatures a low-polluting hybrid engine with an electric motor drive anda Diesel power cycle reciprocating engine.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

According to the first embodiment of the present invention, a zeropollution Rankine cycle thermal engine operating in parallel with a zeroemissions electric motor (also referred to as a hybrid engine) isillustrated in FIG. 1. The Rankine engine consists of a dynamicturbocompressor 10, a reciprocating engine 20, a power transmission 30,a heat exchanger 40, a turboexpander 50, a rectifier 60, a gas generator70, a condenser 80, a recirculating water feed pump 90, a water heater100 and a condenser coolant radiator 110. The electric engine consistsof an alternator 120, a battery 130 and electric motor 140.

Hybrid engine operation begins by starting the electric motor 120 usingthe battery 130 as the energy source. The electric motor 120 drives thereciprocating engine 20 through the power transmission 30 and therebyinitiates the start of the thermal engine that requires a chill-downperiod for the liquefaction equipment consisting of heat exchanger 40,turboexpander 50 and rectifier 60.

Activation of the thermal engine initiates the compression of ambienttemperature air from a surrounding environment entering the dynamiccompressor 2 through an air inlet duct 1. The compressor 2 raises theair to the design discharge pressure. The air then exits through duct 3into intercooler 4 where the heat of compression is removed by externalcooling means 5 (i.e. air, water, Freon, etc.). Condensed water vaporfrom the air is tapped-off by drain 6. After the air exits intercooler 4through duct 7, at a temperature equal to the compressor inlet, itenters the reciprocating compressor 8 and is raised to the designdischarge pressure. The air exits through duct 9 into intercooler 11 andis again cooled to the inlet temperature of the compressor. Thiscompression/cooling cycle is repeated as the air exits intercooler 11through duct 12 and enters reciprocating compressor 13, then exitsthrough duct 14, enters intercooler 15 and exits through duct 16, tocomplete the air pressurization.

The high pressure; ambient temperature air then enters the scrubber 17where any gases or fluids that could freeze during the subsequentliquefaction are removed. These gases and liquids include carbon dioxide(duct 18a and storage tank 18b), oil (line 19a and storage tank 19b) andwater vapor (tap off drain 21). The oil can be from a variety ofsources, such as leakage from the air compression machinery. The dry airthen exits through duct 22 and enters heat exchanger 40 where the air iscooled by returning low temperature gaseous nitrogen.

The dry air is now ready to pass through an air treatment device for theseparation of nitrogen out of the air and to provide nitrogen freeoxygen for combustion as discussed below. The dry air will contain, byweight, 23.1% oxygen, 75.6% nitrogen, 1.285% argon and small traces ofhydrogen, helium, neon, krypton and xenon (total of 0.0013%). Argon hasa liquefaction temperature of 157.5° R, which lies between the nitrogenand oxygen boiling points of 139.9° R and 162.4° R respectively.Therefore argon, which is not removed, will liquefy during theliquefaction process. The remaining traces of gases hydrogen, helium andneon are incondensable at temperatures above 49° R while krypton andxenon will liquefy; however, the trace amounts of these latter gases isconsidered insignificant to the following air liquefaction process.

The dry air then exits through duct 23 and enters the turboexpander 24where the air temperature is further reduced to near liquid airtemperature prior to exiting duct 25 and enters the rectifier 60 (a twocolumn type design is shown). Within the rectifier, if not before, theair is cooled to below the oxygen liquefaction temperature. Preferably,a two column type rectifier 60 is utilized such as that described indetail in the work: The Physical Principles of Gas Liquefaction and LowTemperature Rectification, Davies, first (published by Longmans, Greenand Co. 1949).

The air exits from the lower rectifier heat exchanger 26 through duct 27at liquid air temperature and enters the rectifier's lower column plateswhere the oxygen/nitrogen separation is initiated. Liquid with about 40%oxygen exits through duct 28 and enters the upper rectifier column wherea higher percentage oxygen concentration is generated. Liquid nitrogenat 96% purity is recirculated from the lower rectifier column to theupper column by means of duct 29. Gaseous nitrogen at 99% purity (1%argon) exits through duct 31 and enters heat exchanger 40 where coolingof the incoming air is performed prior to discharging through duct 32 tothe atmosphere at near ambient temperature and pressure. Gaseous orliquid oxygen at 95% purity (5% argon) exits through duct 33 and entersthe turboexpander compressor 34 where the oxygen is pressurized to thedesign pressure. The high pressure oxygen then exits through duct 35 andenters the gas generator 70.

A light hydrocarbon fuel (methane, propane, purified natural gas andlight alcohols such as ethanol and methanol) exits the fuel supply tank37 through duct 38 and enters the reciprocating engine cylinder 39 wherethe fuel is raised to the design discharge pressure. The fuel then exitsthrough duct 41 and enters the gas generator 70 to be mixed with theincoming oxygen at the stoichiometric mixture ratio to achieve completecombustion and maximum hot gas temperature (approximately 6500° R). Thegas generator includes an ignition device, such as a spark plug, toinitiate combustion. While the gas generator 70 is the preferred form offuel combustion device for this embodiment, other fuel combustiondevices could also be used, such as those discussed in the alternativeembodiments below. The products of combustion of these reactants resultin a high purity steam and carbon dioxide gas and a small amount ofgaseous argon (4%).

Following the complete combustion of the high temperature gases,recirculating water is injected into the gas generator 70 through line42 and dilutes the high temperature gases to a lower temperature drivegas acceptable to the reciprocating engine (approximately 2000° R). Thiswater influx also increases a mass flow rate of combustion productsavailable for expansion and power generation. The drive gas then exitsthe gas generator 70 through discharge duct 43, enters reciprocatingcylinder 44, expands and provides power to the power transmission 30.Other combustion product expansion devices can replace the reciprocatingcylinder 44, such as the dynamic turbines discussed in the sixthembodiment below. The gas exits through duct 45, enters the secondcylinder 46, expands and also provides power to the power transmission;the gas exits through duct 47 and powers the dynamic turbine 48 whichdrives the centrifugal compressor 2, which was driven by the electricmotor 140 during start-up, and the alternator 120 to recharge thebattery 130.

The gas then exits through duct 49, enters the water heater 100 whereresidual heat in the gas is transferred to the recirculating water beingpumped by pump 90, the water heater gas exits through duct 51, entersthe condenser 80 at near or below atmospheric pressure, wherecondensation of the steam into water and separation of the carbondioxide takes place. The condensed water exits through line 52, entersthe pump 90 where the pressure of the water is raised to the gasgenerator 70 supply pressure level. A major portion of the pump 90discharge water exits through line 53, enters the water heater 100 whereheat is transferred from the turbine 48 exhaust gas and then exitsthrough line 42 for delivery to the gas generator 70. The remainingwater from the discharge of pump 90 exits through duct 54 and is sprayedthrough nozzles 55 into radiator 110 (evaporative cooling). Coolant forthe condenser gases is recirculated through duct 56 to the radiator 110where heat is rejected to atmospheric air being pumped by fan 57.

The gaseous carbon dioxide, remaining after the condensation of thesteam, exits the condenser 80 through duct 58 and enters thereciprocating cylinder 59, (when the condenser pressure is belowatmospheric) compressed to slightly above atmospheric pressure anddischarged through duct 61. The compressed carbon dioxide can be storedin storage tank 62 and converted to a solid or liquid state for periodicremoval; or the gas can be discharged into the atmosphere when suchexpulsion is permitted.

It should be noted that this hybrid engine generates its own waterrequirements upon demand and thus eliminates the freezing problem of asteam Rankine cycle in a cold (below freezing) environment. Also, theengine generates its oxidizer requirements on demand and thus eliminatesmany safety concerns regarding oxygen storage.

A second embodiment of this invention, illustrated in FIG. 2, features ahybrid engine when using hydrogen in place of a hydrocarbon fuel. Whenusing hydrogen as the fuel no carbon dioxide is generated and only highpurity steam exits from the gas generator 70. Consequently all systemsrelated to carbon dioxide are deleted, and no other changes arebasically required. However, to maintain the same six cylinder engine ofFIG. 1, the hydrogen fuel FIG. 2 exits the fuel supply tank 37 throughduct 63, enters reciprocating engine cylinder 59, exits through duct 64,enters reciprocating engine cylinder 39, exits through duct 41 and isdelivered to the gas generator 70. This permits two stages ofcompression for the low density hydrogen.

A third embodiment of this invention, illustrated in FIG. 3, features adual cycle engine where a Brayton cycle is used for start-up andchill-down of the air liquefaction equipment (Mode I) and a Rankinecycle is used for cruise, idle and continuous duty (Mode II). Toincorporate this feature, high pressure air is tapped-off from cylinder13 (air pressurization as previously described for embodiment one) bymeans of bypass air duct 71 and modulated by valve 72. Also,recirculating water to the gas generator is modulated by means of valve73 to control the combustion temperature of the fuel and oxygen and theexit temperature of the gaseous mixture being delivered to power thecycle through duct 43.

The thermodynamic cycles for these two operating Modes are illustratedin FIG. 4a and FIG. 4b. The working fluid for power cycle operation inMode I consists of steam, carbon dioxide and gaseous air. When operatingin Mode II the working fluid (as discussed in embodiment one and two)consists of steam and carbon dioxide when using hydrocarbon fuel andsteam only when using hydrogen.

An open Brayton cycle, illustrated in FIG. 4a, with two stages ofintercooling the compressed air, 74a, and 74b, is used to power theengine during Mode I and initiates the chill-down of the liquefactionequipment for subsequent Mode II operation of the Rankine cycle withregeneration 75, illustrated in FIG. 4b. Note that this embodimenteliminates the need for an electric motor, battery and alternator.

A fourth embodiment of this invention, illustrated in FIG. 5, includesall the elements of the first embodiment and adds two reheaters 150 and160 to improve the performance of this engine. While two reheaters 150,160 are shown, any number of reheaters can be utilized depending on therequirements of each specific application.

The engine operates as described for the first embodiment but with thefollowing changes. Hot gases exiting reciprocating cylinder 44 exitthrough duct 81, enter the reheater 150 where additional lighthydrocarbon fuel and oxygen is injected through ducts 88 and 89respectively. The heat of combustion of these reactants within thereheater 150 raises the incoming gas temperature to the level of the gasgenerator 70 output. The reheated gas then exits reheater 150 throughduct 82, enters reciprocating cylinder 46, expands and exits throughduct 83 and enters reheater 160 where additional oxygen and fuel isinjected. The heat of combustion of these reactants within the reheater160 again raises the incoming gas temperature to the same level as atthe gas generator 70 output. The heated gas then exits through duct 84and enters the dynamic turbine 48, as described previously in the firstembodiment. Fuel for the reheater 160 is supplied through duct 86. Theoxygen is supplied through duct 87.

A fifth embodiment of this invention, illustrated in FIG. 6, includesall the elements of the second embodiment and adds two reheaters 150 and160 to improve the performance. This engine operates as described forembodiment four except this engine uses hydrogen fuel. The Rankine cycleof these embodiments using regeneration and reheats is illustrated inFIG. 7. Regeneration is illustrated by 91 and the two reheats areillustrated by 92a and 92b.

A sixth embodiment of this invention; illustrated in FIG. 8, is similarto the fourth embodiment featuring reheaters, illustrated in FIG. 5,except all the machinery consists of dynamic type compressors andturbines. This type of machinery is more suitable for higher powerlevels (>1000 SHP) required for rail, ship or standby power systems.

The Rankine engine consists of dynamic turbocompressors 200, 210, and220, a power transmission 230, a heat exchanger 240, a turboexpander250, a rectifier 260, a gas generator 270, a first reheater 280, asecond reheater 290, a water heater 300, a condenser 310, arecirculating pump 320 and a condenser coolant radiator 330. Theelectric engine consists of an alternator 400, a battery 410 andelectric motor 420.

Engine operation begins by starting the electric motor 420 using thebattery 410 as the energy source. The electric motor 420 drives thedynamic compressor 201 through power transmission 230, andsimultaneously, valve 202 is opened and valve 203 is closed. Thisinitiates the start of the engine in a Brayton cycle mode. As enginespeed increases valve 202 is gradually closed and valve 203 is graduallyopened to slowly transition into the Rankine cycle mode and permit theliquefaction equipment to chill down. During this transitional periodthe electric motor 420 is used to maintain scheduled power and speeduntil steady state Rankine cycle conditions are achieved.

During thermal engine activation air enters turbocompressor 201 throughduct 204 and is raised to the design discharge pressure. The air thenexits through duct 205 into intercooler 206 where the heat ofcompression is removed by external cooling means 207 (i.e. air, water,Freon, etc.). Condensed water vapor is tapped-off by drain 208. Afterthe air exits intercooler 206 through duct 209 at a temperature equal tothe compressor inlet, it enters compressor 211 and is raised to thedesign discharge pressure. The air then exits through duct 212 intointercooler 213 and is again cooled to the inlet temperature of thecompressor 201. This compression/cooling cycle is repeated as the airexits intercooler 213 through duct 214, enters compressor 215, thenexits through duct 216, enters intercooler 217 and exits through duct218 to complete the air pressurization.

The high pressure ambient temperature air then enters scrubber 219 wheregases and fluids that are subject to freezing during the liquefactionprocess are removed (i.e. carbon dioxide, water vapor and oil). Carbondioxide exits through duct 221a and is processed and stored in reservoir221b. Oil is drained through duct 222a and stored in reservoir 222b.Water vapor is drained through duct 223 and discharged overboard.

The dry air then exits through duct 224 and enters the heat exchanger240 where the air is cooled by returning gaseous nitrogen. It then exitsthrough duct 225 and enters turboexpander 226 where the air temperatureis further reduced to near liquid air temperature prior to exitingthrough duct 227 and enters the rectifier 260. The air exits from therectifier heat exchanger 228 through duct 229 at liquid air temperatureand enters the rectifier's lower column plates where oxygen/nitrogenseparation is initiated. Liquid with 40% oxygen exits through duct 231and enters the upper rectifier column where a higher percentage oxygenconcentration is generated. Liquid nitrogen at 96% purity isrecirculated from the lower rectifier column to the upper column bymeans of duct 232. Gaseous nitrogen at 99% purity (1% argon) exitsthrough duct 233 and enters the heat exchanger 240 where cooling theincoming dry air is performed prior to discharging through duct 234 tothe atmosphere at near ambient temperature and pressure. Gaseous oxygenor liquid oxygen at 95% purity (5% argon) exits through duct 235 andenters the turboexpander compressor 236 where the oxygen is pressurizedto the design pressure. The high pressure oxygen then exits through duct237 and enters the gas generator 270 through duct 238.

Fuel, i.e. methane, propane, purified natural gas and light alcoholssuch as methanol and ethanol, exits the fuel supply tank 239 throughduct 241 and enters the compressor 242 of turboexpander 250 and israised to the design discharge pressure. The pressurized fuel then exitsthrough duct 243 and enters the gas generator 270 through duct 244 whereit mixes with the incoming oxygen at stoichiometric mixture ratio toachieve complete combustion and maximum hot gas temperature(approximately 6500° R). The products of combustion of these reactantsresult in a high purity steam, carbon dioxide gas and a small amount ofgaseous argon (4%).

Following complete combustion of the high temperature gases,recirculating water is injected into the gas generator through line 245and dilutes the high temperature gases to a lower temperature drive gasacceptable to the dynamic turbine 247 (approximately 2000° R). The drivegas then exits the gas generator 270 through duct 246 and enters theturbine 247 of turbocompressor 220, where the gas expands and powers theair compressor 215 and the carbon dioxide compressor 273. The gas thenexits through duct 248 and enters reheater 280 where the heat extracteddue to the turbine 247 work is replenished. This heat is derived fromthe combustion of added fuel through duct 249 and added oxygen throughduct 251 into reheater 280.

The reheated gas then exits through duct 252 and enters turbine 253 ofturbocompressor 210 and expands to lower pressure. The power produced bythese expanding gases drive the alternator 400 and compressor 211, thenexhaust through duct 254 and enter reheater 290. The heat extracted fromthe gases resulting in the turbine work is replenished with the heat ofcombustion from added fuel through duct 255 and oxygen through duct 256.

The reheated gas then exits through duct 257, enters turbine 258 ofturbocompressor 200 and drives compressor 201 and power transmission230. The turbine exhaust gas then exits through duct 259 and enterswater heater 300 where the residual heat of the turbine 258 exhaust isused to preheat the water that is being recirculated to the gasgenerator 270. The gas then exits through duct 261, enters the condenser310 near or below atmospheric pressure, where condensation of the steaminto water and separation of the carbon dioxide gas occurs.

The condensed water exits through line 262, enters the pump 263 wherethe pressure is raised to the supply level of the gas generator 270. Amajor portion of the discharge water from pump 263 exits through line264, enters the water heater 300 where heat is absorbed from the turbineexhaust gas and then exists through line 245 for delivery to the gasgenerator 270. The remaining water from the discharge of pump 263 exitsthrough line 265 and is sprayed through nozzles 266 into radiator 330for evaporative cooling. Coolant for the condenser gas is recirculatedby pump 267 to the radiator 330 through line 268, where heat is rejectedto atmospheric air being pumped by fan 269.

The gaseous carbon dioxide, remaining from the condensation of steam,exits through duct 271 and enters compressor 273 of turbocompressor 220and is compressed to slightly above atmospheric pressure (when condenserpressure is below atmospheric) and discharged through duct 274 intostorage tank 275. The compressed carbon dioxide can be converted into aliquid or solid state for periodic removal, or the gas can be dischargedinto the atmosphere as local environmental laws permit.

The seventh embodiment of this invention, illustrated in FIG. 9,includes the liquefaction system of the previous embodiments bututilizes the intermittent but spontaneous combustion process of the Ottocycle as the thermal power engine. This embodiment eliminates the needfor the steam condenser and the recirculating water system.

The Otto cycle stem or steam/CO2 thermal engine consists of, in additionto the liquefaction system previously described, a premixer 430 whereoxygen from duct 35, fuel from duct 41 and recirculating steam orsteam/CO2 from duct 301 are premixed in the approximate ratio of 20%, 5%and 75% by weight respectively. These premixed gases are then directedto the reciprocating pistons 302 through duct 303 and ducts 304 wherethey are compressed and ignited with a spark ignition system identicalto current Otto cycle engines. After the power stroke, the steam orsteam/CO2 gases are discharged to the dynamic turbine 48 through ducts305, 306 and then into duct 47. Some of the discharge gases are directedback to the premixer 430 through duct 301. The exhaust gases from thedynamic turbine 48 are then discharged to the atmosphere through duct307.

The eighth embodiment of this invention, illustrated in FIG. 10, issimilar to the seventh embodiment, except a Diesel power cycle is used.In this system a premixer 440 mixes the oxygen from duct 35 with steamor steam/CO2 from duct 308, at an approximate mixture ratio of 23% and77% by weight respectively, and discharges the gaseous mixture to thereciprocating pistons 309 through duct 311 and ducts 312 where themixture is compressed to a high pre-ignition temperature. The highpressure fuel, at approximately 5% of the total weight of the gasmixture in the piston cylinder, is injected through ducts 313 and burnsat approximately constant pressure. If necessary, an ignition device islocated within the combustion cylinder. The hot gases then rapidlyexpand as the piston moves to the bottom of its power stroke. Thesteam/CO2 gases are then discharged into ducts 313 and delivered to thedynamic turbine 48 through duct 47. Some of the discharged gases arediverted to the premixer 440 through the duct 308. The exhaust gasesfrom the dynamic turbine 48 are then discharged into the atmospherethrough duct 307.

What is claimed is:
 1. A hybrid engine consisting of an electric motordrive in parallel with a non-polluting regenerative Rankine cycle engineusing as the working fluid the products of complete combustion of oxygenand a hydrocarbon or simple alcohol (i.e. methanol or ethanol), combinedwith a water quench, said hybrid engine comprising:an electric motormeans connected to a power transmission means, said electric motor meansreceives its electric current from a battery means, said batteryreceives its electric current from an alternator means, said alternatoris driven by a dynamic turbine means; a dynamic compressor means havingan inlet adapted to receive air from a supply and having a discharge,said dynamic compressor including a means to raise the pressure of saidair to a value greater than at said inlet; a first intercooler meansincluding means for receiving said air from said dynamic compressordischarge and having an output and said intercooler including means tocool said air; a reciprocating compressor means having an inlet adaptedto receive air from said first intercooler output and having adischarge, said reciprocating compressor including a means to raise saidpressure of the said air to a value greater than at said inlet; a secondintercooler means including means for receiving said air from saidreciprocating compressor discharge and having an output and said secondintercooler means including means to cool said air; a scrubber means,including means for receiving said air from said second intercooleroutput and having an output, said scrubber having means to remove carbondioxide, water, water vapor and oil form the air; a heat exchanger meanshaving an input adapted to receive said air from said scrubber outputand having an output and said heat exchanger in fluid communication withgaseous nitrogen cooling means; a turbo-expander means having an inputto receive said air from the heat exchanger output and having an exhaustand said turbo-expander including means to reduce the pressure of saidair to a value lower than at said input; a rectifier means having aninput adapted to receive said air from said turbo-expander exhaust andhaving a gaseous nitrogen output and a gaseous oxygen output and saidrectifier having a means to separate the gaseous nitrogen and gaseousoxygen from the said air; said heat exchanger having a gaseous nitrogeninlet adapted to receive said gaseous nitrogen from said rectifieroutput and having a gaseous nitrogen output; a turbo-expander drivendynamic compressor means adapted to receive said gaseous oxygen fromsaid rectifier output and having a discharge, said turbo-expander drivendynamic compressor including means to raise the pressure of said gaseousoxygen to a value greater than at its inlet; a reciprocating compressormeans having an inlet adapted to receive a hydrocarbon type fuel from asupply means and having a discharge and said reciprocating compressorincluding a means to raise said fuel pressure to a value greater than atsaid inlet; a high pressure water pump means having an inlet adapted toreceive lower pressure water from a supply means and having a dischargeand said pump including means to raise the pressure of said water to avalue greater than at said inlet; a gas generator means, including inletmeans for receiving said oxygen from said turbo-expander driven dynamiccompressor discharge, said high pressure fuel from said reciprocatingcompressor discharge and hot water from a high pressure hot water heateroutput, means to completely combust said high pressure oxygen with saidhigh pressure fuel to generate a high temperature gas of steam andcarbon dioxide, means to quench said high temperature gas with said highpressure water to generate a lower temperature mixture of steam andcarbon dioxide gas and having an output; a reciprocating turbine meanshaving an input adapted to receive said gas generator output gas,adapted to deliver power to said power transmission connected to saidelectric motor, and having an exhaust and said reciprocating turbineincluding a means to lower the pressure of said gas to a value lowerthan at said input; a dynamic turbine connected to said dynamic aircompressor, including input means to receive said gas from saidreciprocating turbine exhaust and have an exhaust, said dynamic turbineincluding means to lower the gas pressure to a value lower than at saidinput and said dynamic turbine also connected to said alternator togenerate electricity for said electric motor battery; the said waterheater means including inlet means for receiving said gas from the saiddynamic turbine exhaust, means for receiving cold water from highpressure supply means, means to transfer the said gas heat to the saidwater and having a gas output and a high pressure hot water output; acondenser means including input means to receive the water heater outputgas, means to receive a coolant from a radiator output, means totransfer heat from said gas to said coolant to condense the steam intowater and separate the carbon dioxide gas and output means to dischargethe said condensed water, said carbon dioxide gas and said heatedcoolant; a pump means including and inlet adapted to receive saidcondenser output water, means to raise said water pressure to a valuegreater than at said inlet and have a discharge for said water heatercold water inlet and a discharge for radiator evaporative cooling water;the said radiator means including means for receiving said condenserwarm coolant output, means to cool the warm coolant with ambient air,means for evaporative cooling the ambient air with spray nozzles usingsaid pump evaporative cooling discharge water, and output means todischarge said coolant and a fan means to circulate said ambient air toabsorb heat from said condenser coolant; a reciprocating compressormeans including inlet means to receive gaseous carbon dioxide from thesaid condenser output and having a discharge, means to raise the saidcarbon dioxide pressure to a value greater than at said inlet; a carbondioxide conversion and storage means including means for receiving thereciprocating compressor carbon dioxide discharge and means to convertthe carbon dioxide into a compact liquid or solid state for periodicremoval.
 2. A low or no pollution emitting combustion engine to providepower for various applications such as vehicle propulsion, the enginecomprising in combination:an air inlet configured to receive air from anenvironment surrounding said engine; a source of fuel at least partiallyincluding hydrogen; an air treatment device including an inlet coupledto said air inlet, a means to remove nitrogen from the air, so that theair is primarily oxygen, and an oxygen outlet; a fuel combustion device,said fuel combustion device receiving fuel from said source of fuel andoxygen from said outlet of said air treatment device, said combustiondevice combusting said fuel with said oxygen to produce elevatedpressure and elevated temperature combustion products including steam,said combustion device having a discharge for said combustion products;and a combustion product expansion device coupled to said discharge ofsaid combustion device, said expansion device including means to outputpower from said engine and an exhaust for said combustion products. 3.The engine of claim 2 wherein said engine includes a means to compressthe oxygen and the fuel before the oxygen and the fuel enter saidcombustion device.
 4. The engine of claim 3 wherein said combustiondevice includes a water inlet, said water inlet configured to receivewater from at least one source which includes water originally createdas one of said combustion products exiting said combustion chamber, saidwater inlet placing water into contact with said combustion products formixing with said combustion products and output through said dischargeof said combustion device, whereby a temperature of gases exiting saidcombustion device through said discharge is decreased and a mass flowrate of gases exiting said combustion device through said discharge isincreased.
 5. The engine of claim 4 wherein said means to compress theoxygen includes at least two compressors, each said compressor includingan intercooler therebetween, at least two of said compressors orientedbetween said air inlet and said air treatment device, such that theoxygen is compressed along with other constituents of the air enteringthe air inlet.
 6. The engine of claim 5 wherein at least a portion ofsaid combustion products exiting said exhaust of said combustion productexpansion device are routed to a condenser where the steam within saidcombustion products is condensed to water, said condenser including areturn duct to said water inlet of said combustion device, whereby thesteam/water acts as a working fluid for a Rankine cycle.
 7. The engineof claim 6 wherein each of said compressors are coupled to an electricmotor and battery such that said electric motor and battery can drivesaid compressors for compression of the oxygen, and wherein each of saidcompressors are also coupled to at least one expander in fluidcommunication with said combustion products exiting said discharge ofsaid combustion device, such that said expanders can drive saidcompressors for compression of the oxygen, andwherein said electricmotors include means to charge said battery when said expanders deliverexcess power beyond that necessary to drive said compressors forcompression of the oxygen.
 8. The engine of claim 2 wherein at least onecompressor is oriented between said air inlet and said air treatmentdevice, raising a pressure of the air,wherein at least one intercooleris oriented between a first said compressor and said air treatmentdevice, each said intercooler reducing a temperature of the air passingtherethrough, and wherein said air treatment device includes an expanderdownstream from a last said intercooler, said expander reducing apressure of the air and a temperature of the air to below a condensationpoint of the oxygen within the air, said air treatment device includingsaid oxygen outlet substantially free of nitrogen.
 9. The engine ofclaim 8 wherein said air treatment device includes a nitrogen outlet,and wherein said engine includes a heat transfer device including meansto transfer heat between nitrogen exiting said air treatment devicethrough said nitrogen outlet and air between said expander and said airinlet.
 10. The engine of claim 9 wherein said expander is coupled to anoxygen compressor interposed between said oxygen outlet of said airtreatment device and said combustion device, whereby a pressure of theoxygen is increased.
 11. The engine of claim 10 wherein a scrubber isprovided between said air treatment device and said air inlet to removegases capable of freezing from the air.
 12. The engine of claim 11wherein said air treatment device includes a two column rectifierdownstream from said expander, said rectifier including said oxygenoutlet and said nitrogen outlet.
 13. The engine of claim 7 wherein atleast one of said compressors is oriented between said air inlet andsaid air treatment device, raising a pressure of the air;wherein atleast one intercooler is oriented between a first said compressor andsaid air treatment device,each said intercooler reducing a temperatureof the air passing therethrough; wherein said air treatment deviceincludes an expander downstream from a last said intercooler, saidexpander reducing a pressure of the air and a temperature of the air tobelow a condensation point of the oxygen within the air, said airtreatment device including said oxygen outlet substantially free ofnitrogen; wherein said air treatment device includes a nitrogen outlet,and wherein said engine includes a heat transfer device including meansto transfer heat between nitrogen exiting said air treatment devicethrough said nitrogen outlet and air between said expander and said airinlet; wherein said expander is coupled to an oxygen compressorinterposed between said oxygen outlet of said air treatment device andsaid combustion device, whereby a pressure of the oxygen is increased;wherein a scrubber is provided between said air treatment device andsaid air inlet to remove gases capable of freezing from the air; andwherein said air treatment device includes a two column rectifierdownstream from said expander, said rectifier including said oxygenoutlet and said nitrogen outlet.
 14. The engine of claim 2 wherein saidfuel is a hydrocarbon fuel including hydrogen, carbon and possiblyoxygen,wherein said fuel and said oxygen are provided at astoichiometric ratio needed to produce said combustion productsincluding substantially only steam and carbon dioxide.
 15. The engine ofclaim 14 wherein at least a portion of said combustion products exitingsaid exhaust of said combustion product expansion device are routed to acondenser where the steam within said combustion products is condensedto water, said condenser including a first return duct to said waterinlet of said combustion device, whereby the steam/water acts as aworking fluid for a Rankine cycle;wherein said condenser includes a heattransfer fluid therein for removal of heat from the steam, said heattransfer fluid in fluid communication with an interior of a radiatororiented in the environment surrounding said engine with air from thesurrounding environment passing against an exterior of said radiator andcooling said heat transfer fluid therein; and wherein said condenserincludes a second outlet water duct spraying water into the surroundingenvironment and against said exterior of said radiator for evaporativecooling of said heat transfer fluid within said radiator.
 16. Acombustion engine providing clean power for various applications andfeaturing low NOx production, comprising in combination:a source of air,the air including nitrogen and oxygen; a source of fuel, the fuelincluding hydrogen; an air treatment device having an inlet coupled tosaid source of air, and having an outlet, said air treatment deviceincluding means to remove at least a portion of the nitrogen from theair entering said inlet; a fuel combustion device, said fuel combustiondevice receiving fuel from said source of fuel and air from said outletof said air treatment device, said combustion device combusting saidfuel with the air to produce elevated pressure and elevated temperaturecombustion products including steam, said combustion device having adischarge for said combustion products; and a combustion productexpansion device coupled to said discharge of said combustion device,said expansion device including means to output power from said engine.17. The engine of claim 16 wherein said air treatment device includes anoutlet for excess nitrogen removed by said nitrogen removal means, andwherein a heat exchanging device is interposed between said excessnitrogen outlet of said air treatment device and said source of air,said heat exchanging device including means to cool the air from saidsource of air with the excess nitrogen, without direct contact betweenthe air from said source of air with the excess nitrogen.
 18. The engineof claim 17 wherein said engine includes a means to compress the airfrom said source of air, said expansion device configured to power saidair compression means.
 19. The engine of claim 18 wherein said expansiondevice includes an exhaust for said combustion products, said exhaustincluding a means to separate at least a portion of a steam constituentof said combustion products and means to collect any other combustionproducts, such that only water is discharged from said engine.
 20. Theengine of claim 18 wherein said engine includes a recirculation pathwayinterposed between said exhaust and said fuel combustion device, saidrecirculation pathway providing a means to utilize the combustionproducts from said exhaust to reduce a temperature and increase a massflow rate of gases exiting said discharge of said fuel combustiondevice.